Explain why the bond enthalpy of a Cl Cl bond is greater than that of a Br Br bond
|
|
|
- Miles Norton
- 5 years ago
- Views:
Transcription
1 Q1. The table below gives some values of standard enthalpy changes. Use these values to answer the questions. Name of enthalpy change H ο /kj mol 1 Enthalpy of atomisation of chlorine +121 Electron affinity of chlorine 364 Enthalpy of atomisation of silver +289 First ionisation enthalpy of silver +732 Enthalpy of formation of silver chloride 127 (a) Calculate the bond enthalpy of a Cl Cl bond. (1) (b) Explain why the bond enthalpy of a Cl Cl bond is greater than that of a Br Br bond. (c) Suggest why the electron affinity of chlorine is an exothermic change. (1) (d) The diagram below is an incomplete Born Haber cycle for the formation of silver chloride. The diagram is not to scale. Page 2
2 (i) Complete the diagram by writing the appropriate chemical symbols, with state symbols, on each of the three blank lines. (3) (ii) Calculate a value for the enthalpy of lattice dissociation for silver chloride. (e) The enthalpy of lattice dissociation for silver chloride can also be calculated theoretically assuming a perfect ionic model. (i) Explain the meaning of the term perfect ionic model. (1) (ii) State whether you would expect the value of the theoretical enthalpy of lattice dissociation for silver chloride to be greater than, equal to or less than that for silver bromide. Explain your answer. Theoretical lattice enthalpy for silver chloride... Explanation... Page 3
3 (3) (iii) Suggest why your answer to part (d) (ii) is greater than the theoretical value for the enthalpy of lattice dissociation for silver chloride. (Total 15 marks) Q2. (a) A Born Haber cycle for the formation of calcium sulphide is shown below. The cycle includes enthalpy changes for all steps except step G. (The cycle is not drawn to scale.) Page 4
4 (i) Give the full electronic configuration of the ion S 2 (ii) Suggest why step F is an endothermic process. (iii) Name the enthalpy changes in steps B and D. Step B... Step D... Page 5
5 (iv) Explain why the enthalpy change for step D is larger than that for step C. (v) Use the data shown in the cycle to calculate a value for the enthalpy change for step G. (9) (b) Using a Born Haber cycle, a value of 905 kj mol 1 was determined for the lattice enthalpy of silver chloride. A value for the lattice enthalpy of silver chloride using the ionic model was 833 kj mol 1. Explain what a scientist would be able to deduce from a comparison of these values. (3) (c) Some endothermic reactions occur spontaneously at room temperature. Some exothermic reactions do not occur if the reactants are heated together to a very high temperature. In order to explain the following observations, another factor, the entropy change, ΔS, must be considered. The equation which relates ΔS to ΔH is given below. ΔG = ΔH TΔS (i) Explain why the following reaction occurs at room temperature even though the reaction is endothermic. NaHCO 3(aq) + HCl(aq) NaCl(aq) + H 2O(l) + CO 2(g) Page 6
6 (ii) Explain why the following reaction does not occur at very high temperatures even though the reaction is exothermic. 2SO 2(g) + O 2(g) 2SO 3(g) (6) (Total 18 marks) Q3. A Born Haber cycle for the formation of calcium sulphide is shown below. The cycle includes enthalpy changes for all Steps except Step F. (The cycle is not drawn to scale.) Page 7
7 (a) Give the full electronic arrangement of the ion S 2 (1) (b) Identify the species X formed in Step E. (1) (c) Suggest why Step F is an endothermic process. Page 8
8 (d) Name the enthalpy change for each of the following steps. (i) Step B... (ii) Step D... (iii) Step F... (3) (e) Explain why the enthalpy change for Step D is larger than that for Step C. (f) Use the data shown in the cycle to calculate a value for the enthalpy change for Step F. (Total 11 marks) Q4. (a) A Born Haber cycle for the formation of magnesium(ii) chloride is shown below. Page 9
9 Taking care to note the direction of the indicated enthalpy change and the number of moles of species involved, give each of the enthalpy changes (i) to (v) above. Enthalpy change (i)... Enthalpy change (ii).... Enthalpy change (iii)... Enthalpy change (iv)... Enthalpy change (v)... (5) (b) Write an equation for the decomposition of MgCl(s) into MgCl 2(s) and Mg(s) and use the following data to calculate a value for the enthalpy change of this reaction. H f MgCl(s) = 113 kj mol 1 H f MgCl 2(s) = 653 kj mol 1 Equation... Page 10
10 Calculation... (4) (c) Use the data below to calculate a value for the molar enthalpy of a solution of MgCl 2(s). Lattice formation enthalpy of MgCl 2(s) = 2502 kj mol 1 of Mg 2+ (g) = 1920 kj mol 1 of Cl (g) = 364 kj mol 1 (3) (Total 12 marks) Q5.Which one of the following statements is not correct? A B C The first ionisation energy of iron is greater than its second ionisation energy. The magnitude of the lattice enthalpy of magnesium oxide is greater than that of barium oxide. The oxidation state of iron in [Fe(CN) 6] 3 is greater than the oxidation state of copper in [CuCl 2] D The boiling point of C 3H 8 is lower than that of CH 3CH 2OH (Total 1 mark) Page 11
11 Page 12
Page 2. Define the term electron affinity for chlorine (2)
Q1.(a) Define the term electron affinity for chlorine. (b) Complete this Born Haber cycle for magnesium chloride by giving the missing species on the dotted lines. Include state symbols where appropriate.
(03) WMP/Jun10/CHEM4
Thermodynamics 3 Section A Answer all questions in the spaces provided. 1 A reaction mechanism is a series of steps by which an overall reaction may proceed. The reactions occurring in these steps may
IB Topics 5 & 15 Multiple Choice Practice
IB Topics 5 & 15 Multiple Choice Practice 1. Which statement is correct for this reaction? Fe 2O 3 (s) + 3CO (g) 2Fe (s) + 3CO 2 (g) ΔH = 26.6 kj 13.3 kj are released for every mole of Fe produced. 26.6
(2)
(a) Define the term electron affinity for chlorine. (b) Complete this Born Haber cycle for magnesium chloride by giving the missing species on the dotted lines. Include state symbols where appropriate.
1.8 Thermodynamics. Lattice formation enthalpy Enthalpy change when 1 mole of a solid ionic compound is formed from its gaseous ions
1.8 Thermodynamics Review: In 1.3 we looked at ionic bonding and learned that: Giant ionic lattice structure Ionic bonding: Strong electrostatic force of attraction between oppositely charged ions that
Topic 10 Thermodynamics Revision Notes
1) Enthalpy Changes Topic 10 Thermodynamics Revision Notes An enthalpy change is a change in heat energy measured at constant pressure. Enthalpy changes refer to the chemicals not the surroundings. The
AQA A2 CHEMISTRY TOPIC 5.1 THERMODYNAMICS BOOKLET OF PAST EXAMINATION QUESTIONS
AQA A2 CHEMISTRY TOPIC 5.1 THERMODYNAMICS BOOKLET OF PAST EXAMINATION QUESTIONS 1 1. A Born Haber cycle for the formation of calcium sulphide is shown below. The cycle includes enthalpy changes for all
15.2 Born-Haber Cycles
15.2 Born-Haber Cycles 15.2.1 - Define and apply the terms lattice enthalpy and electron affinity Lattice Enthalpy The energy required to completely separate one mole of a solid ionic compound into its
5.2 Energy. N Goalby chemrevise.org Lattice Enthalpy. Definitions of enthalpy changes
5.2 Energy 5.2.1 Lattice Enthalpy Definitions of enthalpy changes Enthalpy change of formation The standard enthalpy change of formation of a compound is the energy transferred when 1 mole of the compound
1.8 Thermodynamics. N Goalby chemrevise.org. Definitions of enthalpy changes
1.8 Thermodynamics Definitions of enthalpy changes Enthalpy change of formation The standard enthalpy change of formation of a compound is the energy transferred when 1 mole of the compound is formed from
12A Entropy. Entropy change ( S) N Goalby chemrevise.org 1. System and Surroundings
12A Entropy Entropy change ( S) A SPONTANEOUS PROCESS (e.g. diffusion) will proceed on its own without any external influence. A problem with H A reaction that is exothermic will result in products that
UNIVERSITY OF SIERRA LEONE FOURAH BAY COLLEGE. FIRST EXAMINATION FOR THE DEGREE OF B. Sc. HONOURS LEVEL I SECOND SEMESTER EXAMINATION
UNIVERSITY OF SIERRA LEONE FOURAH BAY COLLEGE CHEM 121 INSTRUCTIONS: FIRST EXAMINATION FOR THE DEGREE OF B. Sc. HONOURS LEVEL I SECOND SEMESTER EXAMINATION WEDNESDAY 12 th SEPTEMBER 2018 13.30 16.45 CHEM
, is formed when iron metal reacts with. iodine. The table below shows enthalpy changes involving iron, iodine and iron(ii) iodide.
1 Iron(II) iodide, FeI 2, is formed when iron metal reacts with (a) iodine. The table below shows enthalpy changes involving iron, iodine and iron(ii) iodide. Enthalpy change / kj mol 1 Formation of iron(ii)
[2] The table below shows the enthalpy changes that are needed to determine the enthalpy change of hydration of magnesium ions.
![[2] The table below shows the enthalpy changes that are needed to determine the enthalpy change of hydration of magnesium ions.](/thumbs/81/83379763.jpg "[2] The table below shows the enthalpy changes that are needed to determine the enthalpy change of hydration of magnesium ions.")
1 Born Haber cycles provide a model that chemists use to determine unknown enthalpy changes from known enthalpy changes. In this question, you will use a Born Haber cycle to determine an enthalpy change
lattice formation from gaseous ions
BORN HABER CYCLES The Born Haber cycles is an adaption of Hess s law to calculate lattice enthalpy from other data The lattice enthalpy cannot be determined directly. We calculate it indirectly by making
The chemical potential energy of a substance is known as its ENTHALPY and has the symbol H.
Enthalpy Changes The chemical potential energy of a substance is known as its ENTHALPY and has the symbol H. During chemical reactions, the enthalpy can increase or decrease. The change in enthalpy during
Complete the diagram by writing the formulae, including state symbols, of the appropriate species on each of the three blank lines.
(a) The diagram is a Born Haber cycle for potassium oxide, K 2 O. The diagram is not to scale and not fully labelled. (i) Complete the diagram by writing the formulae, including state symbols, of the appropriate
CHERRY HILL TUITION AQA CHEMISTRY A2 PAPER Section A. Answer all questions in the spaces provided.
2 Section A Answer all questions in the spaces provided. 1 This question is about bond dissociation enthalpies and their use in the calculation of enthalpy changes. 1 (a) Define bond dissociation enthalpy
Thermodynamics. Standard enthalpy change, H
Standard enthalpy change, H Thermodynamics Enthalpy change, H, is defined as the heat energy change measured under conditions of constant pressure. The value of the enthalpy change for a particular reaction
Worksheet 5.2. Chapter 5: Energetics fast facts
Worksheet 52 Chapter 5: Energetics fast facts 51 Exothermic and endothermic reactions Energetics deals with heat changes in chemical reactions Enthalpy is the amount of heat energy contained in a substance
Topic 05 Energetics : Heat Change. IB Chemistry T05D01
Topic 05 Energetics 5.1-5.2: Heat Change IB Chemistry T05D01 5.1 Exothermic and endothermic reactions - 1 hour 5.1.1 Define the terms exothermic reaction, endothermic reaction and standard enthalpy change
CHERRY HILL TUITION AQA CHEMISTRY A2 PAPER Section A (2 marks) (1 mark) (Extra space) Property
2 Section A Answer all questions in the spaces provided. 1 (a) Define the term lattice enthalpy of dissociation. 1 (b) Lattice enthalpy can be calculated theoretically using a perfect ionic model. Explain
ZAHID IQBAL WARRAICH
Q1 (a) (i) What is meant by the term lattice energy? (ii) Write an equation to represent the lattice energy of MgO. (b) The apparatus shown in the diagram can be used to measure the enthalpy change of
Iron is extracted from iron(iii) oxide using carbon at a high temperature.
Q1.(a) Iron is extracted from iron(iii) oxide using carbon at a high temperature. (i) State the type of reaction that iron(iii) oxide undergoes in this extraction... Write a half-equation for the reaction
AS Paper 1 and 2 Energetics
AS Paper 1 and 2 Energetics Q1.Nitric acid is produced industrially from ammonia, air and water using the following sequence of reactions: 4NH 3 (g) + 5O 2(g) 4NO(g) + 6H 2O(g) H = 909 kj mol 1 (2) 2NO(g)
Enthalpy and Entropy
F35 Equilibria, Energetics & Elements Enthalpy and Entropy 1. (a) 1s s p 6 3s 3p 6 1 (b) S (g) 1 (c) The negative S ion 1 repels the electron being added 1 (d) (i) Enthalpy of atomisation of sulphur 1
5.2.1 Answers Lattice Enthalpy 2012
5.2.1 Answers Lattice Enthalpy 2012 Introduction In this topic we will construct a Born-Haber cycle (or lattice enthalpy cycle) which allows us to calculate numerical values for processes which occur in
5.1 EXAM QUESTIONS MS
5.1 EXAM QUESTIONS MS 1. (a) 1s s p 6 3s 3p 6 1 (b) S (g) 1 (c) The negative S ion 1 repels the electron being added 1 (d) (i) Enthalpy of atomisation of sulphur 1 (ii) Second ionisation enthalpy of calcium
CHEM5. (JAN12CHEM501) WMP/Jan12/CHEM5. General Certificate of Education Advanced Level Examination January 2012
Centre Number Surname Candidate Number For Examiner s Use Other Names Candidate Signature Examiner s Initials General Certificate of Education Advanced Level Examination January 2012 Question 1 2 Mark
CHEM 121 INTRODUCTION TO ENERGETICS, THERMODYNAMICS AND KINETICS
DEPARTMENT OF CHEMISTRY FOURAH BAY COLLEGE UNIVERSITY OF SIERRA LEONE CHEM 121 INTRODUCTION TO ENERGETICS, THERMODYNAMICS AND KINETICS CREDIT HOURS 2.0 MINIMUM REQUIREMENTS C6 in WASSCE Chemistry or equivalent
Topic 5.1 THERMODYNAMICS. Born-Haber Cycles Solubility of Ionic Compounds in Water Entropy Changes
Topic 5.1 THERMODYNAMICS Born-Haber Cycles Solubility of Ionic Compounds in Water Entropy Changes CALCULATING ENTHALPY CHANGES a) atomisation enthalpy and bond dissociation enthalpy The enthalpy change
D A(g) + B(g) C(g) endothermic (Total 1 mark) [Cu(H 2O) 6] H 2NCH 2CH 2NH 2 [Cu(H 2NCH 2CH 2NH 2) 2(H 2O) 2] H 2O (Total 1 mark)
![D A(g) + B(g) C(g) endothermic (Total 1 mark) [Cu(H 2O) 6] H 2NCH 2CH 2NH 2 [Cu(H 2NCH 2CH 2NH 2) 2(H 2O) 2] H 2O (Total 1 mark)](/thumbs/93/113959133.jpg "D A(g) + B(g) C(g) endothermic (Total 1 mark) [Cu(H 2O) 6] H 2NCH 2CH 2NH 2 [Cu(H 2NCH 2CH 2NH 2) 2(H 2O) 2] H 2O (Total 1 mark)")
Q1.Which one of the equations below represents a reaction that is feasible at all temperatures? P(s) Q(s) + R(g) endothermic 2L(g) + M(g) 2N(g) exothermic S(g) 2T(g) exothermic (g) + (g) (g) endothermic
Page 2. (b) Mg 2+ (g) + 2e + 2Cl(g) (1) (M5)
M.(a) The enthalpy change / heat energy change / ΔH for the formation of one mole of (chloride) ions from (chlorine) atoms Allow enthalpy change for Cl + e Cl Do not allow energy change ionisation energy
Kinetics & Equilibrium Review Packet. Standard Level. 1. Which quantities in the enthalpy level diagram are altered by the use of a catalyst?
Kinetics & Equilibrium Review Packet Standard Level 1. Which quantities in the enthalpy level diagram are altered by the use of a catalyst? Enthalpy I II III Time A. I and II only B. I and III only C.
Born-Haber Calculations
Born-Haber Calculations Hess' law Hess' law is the fundamental basis behind the calculation of all thermodynamic quantities. The principle can be applied to ionic systems by considering the different energy
A. 2.5 B. 5.0 C. 10. D. 20 (Total 1 mark) 2. Consider the following reactions. N 2 (g) + O 2 (g) 2NO(g) 2NO 2 (g) 2NO(g) + O 2 (g)
1. When 100 cm 3 of 1.0 mol dm 3 HCl is mixed with 100 cm 3 of 1.0 mol dm 3 NaOH, the temperature of the resulting solution increases by 5.0 C. What will be the temperature change, in C, when 50 cm 3 of
1 P a g e h t t p s : / / w w w. c i e n o t e s. c o m / Chemistry (A-level)
1 P a g e h t t p s : / / w w w. c i e n o t e s. c o m / Lattice energy (Chapter 19 TB) Chemistry (A-level) Lattice energy is the enthalpy change when 1 mole of an ionic compound is formed from its gaseous
2815/01 CHEMISTRY. Trends and Patterns. OXFORD CAMBRIDGE AND RSA EXAMINATIONS Advanced GCE
OXFORD CAMBRIDGE AND RSA EXAMINATIONS Advanced GCE CHEMISTRY Trends and Patterns 2815/01 Monday 26 JUNE 2006 Morning 1 hour Candidates answer on the question paper. Additional materials: Data Sheet for
CHEM5. (JAN13CHEM501) WMP/Jan13/CHEM5. General Certificate of Education Advanced Level Examination January 2013
Centre Number Surname Candidate Number For Examiner s Use Other Names Candidate Signature Examiner s Initials General Certificate of Education Advanced Level Examination January 2013 Question 1 2 Mark
CH 223 Sample Exam Exam II Name: Lab Section:
Exam II Name: Lab Section: Part I: Multiple Choice Questions (100 Points) Use a scantron sheet for Part I. There is only one best answer for each question. 1. Which of the following equations is the solubility
Entropy. An endothermic reaction can be compared to a ball spontaneously rolling uphill or a pencil lying down springing upright.
Entropy Exothermic and Endothermic Reactions Most chemical reactions give out heat energy as they take place, so the products have less energy (and so are more stable) than the reactants. These are exothermic
13 Energetics II. Eg. Na (g) Na + (g) + e - ΔH = +550 kj mol -1
13 Energetics II First ionisation energy I(1) or IE (1): the energy required to remove one mole of electrons from one mole of the gaseous atoms of an element to 1 mole of gaseous monopositive ions. Eg.
1. (i) Give an equation for the dissociation of propanoic acid and hence an expression for its dissociation constant, K a. ...
1. (i) Give an equation for the dissociation of propanoic acid and hence an expression for its dissociation constant, K a.... At 5 C K a for propanoic acid is 1.30 10 5 mol dm 3. Find the ph of a solution
In previous chapters we have studied: Why does a change occur in the first place? Methane burns but not the reverse CH 4 + 2O 2 CO 2 + 2H 2 O
Chapter 19. Spontaneous Change: Entropy and Free Energy In previous chapters we have studied: How fast does the change occur How is rate affected by concentration and temperature How much product will
Exam Style Questions
Calderglen High School Chemistry Department CfE Higher Chemistry Unit 1: Chemical Changes and Structure Exam Style Questions 1 1.1 Controlling the Rate 1. The graph shows how the rate of a reaction varies
Advanced Subsidiary Unit 1: The Core Principles of Chemistry
Write your name here Surname Other names Pearson Edexcel International Advanced Level Centre Number Chemistry Advanced Subsidiary Unit 1: The Core Principles of Chemistry Candidate Number Friday 26 May
Class XI Chapter 6 Thermodynamics Chemistry
Class XI Chapter 6 Chemistry Question 6.1: Choose the correct answer. A thermodynamic state function is a quantity (i) used to determine heat changes (ii) whose value is independent of path (iii) used
2 Answer all the questions. CO, in the presence of aqueous hydrochloric acid, HCl(aq).
2 Answer all the questions. 1 A student investigates the reaction between iodine, I 2, and propanone, (CH 3 ) 2 CO, in the presence of aqueous hydrochloric acid, HCl(aq). The results of the investigation
1. The reaction between solid barium hydroxide and solid ammonium chloride can be represented by the equation below.
1. The reaction between solid barium hydroxide and solid ammonium chloride can be represented by the equation below. Ba(OH) 2 (s) + 2NH 4 Cl(s) BaCl 2 (s) + 2NH 3 (g) + 2H 2 O(l) ΔH ο = +51.1 kj mol 1
CHEM5 (JUN13CHEM501) General Certificate of Education Advanced Level Examination June Unit 5 Energetics, Redox and Inorganic Chemistry
Centre Number Surname Candidate Number For Examiner s Use Other Names Candidate Signature Examiner s Initials General Certificate of Education Advanced Level Examination June 2013 Question 1 2 Mark Chemistry
ENTROPY. Definition: Entropy is the quantitative measure of disorder in a system
ENTROPY Definition: Entropy is the quantitative measure of disorder in a system This depends not only on the degree to which the molecules are randomly arranged, but also on the random distribution of
Q = Enthalpy change for the formation of calcium chloride (P). D Twice the enthalpy change of atomization of chlorine (S).
1 What is the equation for the first electron affinity of sulfur? S(s) + e S (g) S(g) + e S (g) S(s) S + (g) + e S(g) S + (g) + e 2 The diagram shows a orn-haber cycle for calcium chloride. It is not drawn
5 Chemical Energetics
5 Chemical Energetics Definition: Enthalpy change is the amount of heat energy taken in or given out during any change in a system provided the pressure is constant. In an exothermic change energy is transferred
QUESTIONSHEETS ENERGETICS II ENTHALPY OF ATOMISATION ENTROPY AND FREE ENERGY CHANGE PRINCIPLES OF ELECTROCHEMICAL CELLS
CHEMISTRY QUESTIONSHEETS A2 Level A2 TOPIC 17 ENERGETICS II Questionsheet 1 Questionsheet 2 Questionsheet 3 Questionsheet 4 Questionsheet 5 Questionsheet 6 Questionsheet 7 Questionsheet 8 Questionsheet
c) Explain the observations in terms of the DYNAMIC NATURE of the equilibrium system.
Chemical Equilibrium - Part A: 1. At 25 o C and 101.3 kpa one mole of hydrogen gas and one mol of chlorine gas are reacted in a stoppered reaction vessel. After a certain time, three gases are detected
Paper Reference. Thursday 23 June 2005 Afternoon Time: 1 hour 30 minutes
Centre No. Candidate No. Paper Reference(s) 6244/01 Edexcel GCE Chemistry Advanced Unit Test 4 Thursday 23 June 2005 Afternoon Time: 1 hour 30 minutes Materials required for examination Nil Paper Reference
Unit 5 - Energetics. Exo vs Endo, Enthalpy, Hess s Law, Born-Haber, Entropy, Spontaneity (Gibbs Free Energy)
Unit 5 - Energetics Exo vs Endo, Enthalpy, Hess s Law, Born-Haber, Entropy, Spontaneity (Gibbs Free Energy) Heating some water... You re job is to figure out how we can find the heat change for one mole
Q1. (a) Explain the meaning of the terms mean bond enthalpy and standard enthalpy of formation. Mean bond enthalpy
Q1. (a) Explain the meaning of the terms mean bond enthalpy and standard enthalpy of formation. Mean bond enthalpy......... Standard enthalpy of formation............ (5) (b) Some mean bond enthalpies
2 Answer all the questions. 1 Born Haber cycles can be used to calculate enthalpy changes indirectly.
2 Answer all the questions. 1 Born Haber cycles can be used to calculate enthalpy changes indirectly. (a) The table below shows enthalpy changes for a Born Haber cycle involving potassium sulfide, K 2
TOPIC 17 ANSWERS & MARK SCHEMES QUESTIONSHEET 1 ENTHALPY OF ATOMISATION
QUESTIONSHEET 1 ENTHALPY OF ATOMISATION a) The standard enthalpy of atomisation of an element is the energy required (½) to produce 1 mole (½) of gaseous atoms (½) from the element in its standard state
OCR Chemistry A H432
All the energy changes we have considered so far have been in terms of enthalpy, and we have been able to predict whether a reaction is likely to occur on the basis of the enthalpy change associated with
Energy Relationships in Chemical Reactions
Energy Relationships in Chemical Reactions What is heat? What is a state function? What is enthalpy? Is enthalpy a state function? What does this mean? How can we calculate this? How are the methods the
NH + Chemistry 6A F2007. Dr. J.A. Mack 10/19/07. Draw and describe the following molecule: (2) = 16 electrons needed
Chemistry 6A F007 Dr. J.A. Mack 10/19/07 10/19/07 Dr. Mack. CSUS 1 Draw and describe the following molecule: 8 + 4() = 16 electrons needed 5 + 4(1) 1 = 8 electrons needed 16 8 = 8 electrons shared N must
Tuesday 9 October 2018
Please check the examination details below before entering your candidate information Candidate surname Other names Pearson Edexcel International Advanced Level Centre Number Tuesday 9 October 2018 Morning
Thermodynamics. For the process to occur under adiabatic conditions, the correct condition is: (iii) q = 0. (iv) = 0
Thermodynamics Choose the correct answer. A thermodynamic state function is a quantity (i) used to determine heat changes (ii) whose value is independent of path (iii) used to determine pressure volume
1 Two white powders, A and B, known to be Group 2 carbonates, are investigated.
1 Two white powders, A and B, known to be Group 2 carbonates, are investigated. (a) (i) The presence of the carbonate ion is usually confirmed using a simple test carried out in two stages at room temperature.
KOH(aq) + HNO 3 (aq) KNO 3 (aq) + H 2 O(l) A 52 B 26 C +26 D +52. (Total for Question = 1 mark) 2 Calculate the enthalpy change, in kj mol _ 1
1 When 0.1 mol of aqueous potassium hydroxide was added to 0.1 mol of nitric acid, 5200 J were transferred to the surroundings. What is the enthalpy change, in kj mol 1, for this reaction? 52 26 C +26
AS Paper 1 and 2 Energetics MARK SCHEME
AS Paper and 2 Energetics MARK SCHEME M.D [] M2.D [] M3.A [] M4.D [] M5.B [] M6.C [] M7. (a) (Energy required) to break a given covalent bond () averaged over a range of compounds () Penalise first mark
15.2 Born-Haber Cycle
15.2 Born-Haber Cycle Our calculations of enthalpies so far have involved covalent substances. Now we need to look at the enthalpy changes involved in the formation of giant ionic lattices. Lattice enthalpy
Answers. Chapter 5. Exercises
Answers Chapter 5 Exercises 1 B 2 B 3 A 4 D 5 C 6 q = mc T, so T = q mc = 100 = 7.25 C 100 0.138 T = 25.0 + 7.25 = 32.3 C 7 A 8 A 9 C 10 (a) ΔT = 36.50 25.85 = 10.65 C (or K) (b) q = mc T q = m(h 2 O)
N10/4/CHEMI/SP2/ENG/TZ0/XX CHEMISTRY STANDARD LEVEL PAPER 2. Thursday 11 November 2010 (afternoon) Candidate session number.
N10/4/CHEMI/SP2/ENG/TZ0/XX 88106105 CHEMISTRY STANDARD LEVEL PAPER 2 Thursday 11 November 2010 (afternoon) 1 hour 15 minutes 0 0 Candidate session number INSTRUCTIONS TO CANDIDATES Write your session number
Elements in the Periodic Table show a periodic trend in atomic radius. In your answer you should use appropriate technical terms, spelled correctly.
1 The Periodic Table is arranged in periods and groups (a) Elements in the Periodic Table show a periodic trend in atomic radius State and explain the trend in atomic radius from Li to F In your answer
b1. Give the Lewis dot symbol associated with elemental magnesium b2. Give the Lewis dot symbol associated with the magnesium ion.
1. For the following reaction: N2+ H2O a. Write the balanced chemical equation. b. Estimate the enthalpy of the balanced reaction in kj/mol nitrogen using the bond energies given below. c. Estimate the
TERMS AND DEFINITIONS IN THERMOCHEMISTRY
(v.2.0 16/3/90 8hrs.) TERMS AND DEFINITIONS IN THERMOCHEMISTRY (v.2.1 12/4/90 2hrs.) 1) ENTHALPY CHANGE ( H) This is the same as the heat change involved in a process (provided the initial and final states
2 Answer all the questions. How many neutrons are there in an atom of chlorine-37?... [1] How many electrons are needed to fill one orbital?
![2 Answer all the questions. How many neutrons are there in an atom of chlorine-37?... [1] How many electrons are needed to fill one orbital?](/thumbs/87/96035070.jpg "2 Answer all the questions. How many neutrons are there in an atom of chlorine-37?... [1] How many electrons are needed to fill one orbital?")
2 Answer all the questions 1 The answer to each part of this question is a number (a) (i) How many neutrons are there in an atom of chlorine-37? [1] (ii) How many electrons are needed to fill one orbital?
İTÜ GELİŞTİRME VAKFI ÖZEL EKREM ELGİNKAN LİSESİ. Term Lesson Unit Subject Date. 2nd Chemistry Unit Review
İTÜ GELİŞTİRME VAKFI ÖZEL EKREM ELGİNKAN LİSESİ Term Lesson Unit Subject Date 2nd Chemistry Unit 5-6-7 Review 25.04-03.05 2015 Name- Surname Class: 10-IB Number: 1. What is the function of iron in the
Name AP CHEM / / Collected AP Exam Essay Answers for Chapter 16
Name AP CHEM / / Collected AP Exam Essay Answers for Chapter 16 1980 - #7 (a) State the physical significance of entropy. Entropy (S) is a measure of randomness or disorder in a system. (b) From each of
Advanced Subsidiary Unit 1: The Core Principles of Chemistry
Write your name here Surname Other names Pearson Edexcel International Advanced Level Centre Number Chemistry Advanced Subsidiary Unit 1: The Core Principles of Chemistry Candidate Number Thursday 9 January
Chapter 19 Chemical Thermodynamics
Chapter 19 Chemical Thermodynamics Spontaneous Processes Entropy and the Second Law of Thermodynamics The Molecular Interpretation of Entropy Entropy Changes in Chemical Reactions Gibbs Free Energy Free
ANSWERS IB Chemistry HL Yr 1 Unit 7 Energetics
ANSWERS IB Chemistry HL Yr 1 Unit 7 Energetics Review Part 1 Multiple Choice 1 When potassium persulphate, K 2 S 2 O 8, is dissolved in water the solution becomes warm Which of the following statements
Chemical thermodynamics and bioenergetics
Chemical thermodynamics and bioenergetics Thermodynamics is a branch of physics that studies energy, the forms of its transformation, and the laws controlling its properties. Basic Concepts and Definitions.
2 Answer all the questions.
2 Answer all the questions. 1 Born Haber cycles provide a model that chemists use to determine unknown enthalpy changes from known enthalpy changes. In this question, you will use a Born Haber cycle to
Chapter Eighteen. Thermodynamics
Chapter Eighteen Thermodynamics 1 Thermodynamics Study of energy changes during observed processes Purpose: To predict spontaneity of a process Spontaneity: Will process go without assistance? Depends
Advanced Subsidiary Unit 1: The Core Principles of Chemistry. Wednesday 11 January 2017 Morning Time: 1 hour 30 minutes
Write your name here Surname Other names Pearson Edexcel International Advanced Level Centre Number Chemistry Advanced Subsidiary Unit 1: The Core Principles of Chemistry Candidate Number Wednesday 11
ENERGETICS. Energy changes which take place during a chemical reaction can be represented on an energy (enthalpy) profile diagram.
ENERGETICS All types of chemical reaction involve changes in energy. When energy is emitted it can take a number of forms, but the most common form is as heat energy. Heat energy is called enthalpy. Enthalpy
Lecture #13. Chapter 17 Enthalpy and Entropy
Lecture #13 Chapter 17 Enthalpy and Entropy First Law of Thermodynamics Energy cannot be created or destroyed The total energy of the universe cannot change Energy can be transferred from one place to
Paper Reference. Tuesday 23 January 2007 Morning Time: 1 hour 30 minutes
Centre No. Candidate No. Paper Reference(s) 6244/01 Edexcel GCE Chemistry Advanced Unit Test 4 Tuesday 23 January 2007 Morning Time: 1 hour 30 minutes Materials required for examination Nil A calculator
CHEMISTRY 2815/01. Trends and Patterns. OXFORD CAMBRIDGE AND RSA EXAMINATIONS Advanced GCE
OXFORD CAMBRIDGE AND RSA EXAMINATIONS Advanced GCE CHEMISTRY 2815/01 Trends and Patterns Tuesday 25 JANUARY 2005 Afternoon 1 hour Candidates answer on the question paper. Additional materials: Data Sheet
Second Law of Thermodynamics
Second Law of Thermodynamics First Law: the total energy of the universe is a constant Second Law: The entropy of the universe increases in a spontaneous process, and remains unchanged in a process at
2 Answer all the questions. 1 Born Haber cycles can be used to determine lattice enthalpies of ionic compounds
2 Answer all the questions. 1 Born Haber cycles can be used to determine lattice enthalpies of ionic compounds. (a) Define, in words, the term lattice enthalpy............. [2] (b) The Born Haber cycle
13 Energetics Answers to end-of-chapter questions
Pages 253 254 Questions 1 2 [e] Always label a Hess s law diagram with either ΔH or the values of ΔH. ΔH f (C 2 H 4 ) + ΔH f (H 2 O) + ΔH r = ΔH f (C 2 H 5 OH) +52.3 + ( 286) + ΔH r = 278 ΔH r = 278 52.3
1. Parts of Chemical Reactions. 2 H 2 (g) + O 2 (g) 2 H 2 O(g) How to read a chemical equation
Unit 6 Chemical Reactions 1. Parts of a Chemical Reaction 2. Indicators of a Chemical Reaction 3. Enthalpy 4. Balancing Chemical Equations 5. Word Equations 6. Classifying Chemical Reactions 7. Predicting
F321: Atoms, Bonds and Groups Redox
F321: Atoms, Bonds and Groups Redox 39 Marks 1. The element strontium forms a nitrate, Sr(NO 3 ) 2, which decomposes on heating as shown below. 2Sr(NO 3 ) 2 (s) 2SrO(s) + 4NO 2 (g) + O 2 (g) Using oxidation
Thermodynamics Born- Haber cycles
Thermodynamics Born- Haber cycles Born Haber cycles Is when Hess s Law is extended towards ionic compounds. We usually calculate Enthalpy of formation for substances using bond energy data. But, we cannot
General Chemistry I Concepts
Thermodynamics Thermodynamics The Three Laws of Thermodynamics (18.1) Spontaneous Processes (18.2) Entropy (18.3) The Second Law of Thermodynamics (18.4) Gibbs Free Energy (18.5) Free Energy and Chemical
Assessment Schedule 2017 Chemistry: Demonstrate understanding of thermochemical principles and the properties of particles and substances (91390)
NCEA Level 3 Chemistry (91390) 2017 page 1 of 6 Assessment Schedule 2017 Chemistry: Demonstrate understanding of thermochemical principles and the properties of particles and substances (91390) Evidence
2. Relative molecular mass, M r - The relative molecular mass of a molecule is the average mass of the one molecule when compared with
Chapter 3: Chemical Formulae and Equations 1. Relative atomic mass, A r - The relative atomic mass of an element is the average mass of one atom of an element when compared with mass of an atom of carbon-12
(02) Section A. Answer all questions in the spaces provided.
2 Section A Answer all questions in the spaces provided. 1 Thermodynamics can be used to investigate the changes that occur when substances such as calcium fluoride dissolve in water. 1 (a) Give the meaning
Representing Chemical Change
Representing Chemical Change As we have already mentioned, a number of changes can occur when elements react with one another. These changes may either be physical or chemical. One way of representing
Paper Reference. Tuesday 22 January 2008 Morning Time: 1 hour 30 minutes
Centre No. Candidate No. Paper Reference(s) 6244/01 Edexcel GCE Chemistry Advanced Unit Test 4 Tuesday 22 January 2008 Morning Time: 1 hour 30 minutes Materials required for examination Nil Candidates